The objective is to publish in concert with histologists in human medicine and zoology, a common, comparative mammalian histological nomenclature based on the human species but also including terms unique to domestic, laboratory, and exotic animal species. The human and veterinary histology nomenclature groups, which worked separately for five or more years on their respective Nomina Histologica (NH) and Nomina Histologica Veterinaria (NHV) lists of terms, now have a tentative agreement to join their efforts. Through separate and joint working meetings and individual revision work the nomina controversia in the nomenclature terms common to the NH and NHV will be resolved. Work on veterinary histology terms and those relating to laboratory and exotic animal species will comprise our second principal effort. It is projected that members of this project (and other members of our NHV subcommittee) working together with our NH subcommittee counterparts can produce a common comparative mammalia by the time of the next meeting of the World Association of Veterinary Anatomists (in 1979) and International Congress of Anatomists (in 1980).